A fuel pump comprises a cam assembly having a lobe, and a body assembly including a cavity for receiving the cam assembly. The body assembly includes both a body portion and a cover portion that cooperatively form the cavity. The body portion includes a lobe cavity, an engagement surface and an opening at the cavity, with the cover portion including a respective engagement surface and opening. The engagement surfaces are mated together with the cam assembly disposed in the cavity and extending through the openings, and is configured to rotate in the cavity with the lobe disposed in the lobe cavity. A groove is formed in one of the engagement surfaces of the body portion or cover portion for receiving a seal cap at least partially therein adjacent the lobe cavity.

A hydraulic unit, in particular a hydraulic unit for a slip-controllable vehicle brake system, includes a housing block, a pump, and a damping device. The pump has an intake side and a delivery side. The housing block has a pump receptacle that holds the pump, a first fluid duct that intersects the pump receptacle in a region of the delivery side of the pump, and a second fluid duct opening into the pump receptacle in the region of the delivery side of the pump, and a first separation point that seals off the first fluid duct from the second fluid duct. The damping device damps pulsations and reduces operating noise of the hydraulic unit without (i) having a detrimental effect on functional characteristics of the unit, in particular on pressure build-up dynamics of the vehicle brake system, or without (ii) jeopardizing a compact construction of the hydraulic unit.

A hydraulic unit, in particular a hydraulic unit for a slip-controllable vehicle brake system, includes a housing block, a pump, and a damping device. The pump has an intake side and a delivery side. The housing block has a pump receptacle that holds the pump, a first fluid duct that intersects the pump receptacle in a region of the delivery side of the pump, and a second fluid duct opening into the pump receptacle in the region of the delivery side of the pump, and a first separation point that seals off the first fluid duct from the second fluid duct. The damping device damps pulsations and reduces operating noise of the hydraulic unit without (i) having a detrimental effect on functional characteristics of the unit, in particular on pressure build-up dynamics of the vehicle brake system, or without (ii) jeopardizing a compact construction of the hydraulic unit.

A piston pump as a high-pressure fuel pump of a common rail system includes: a pump cylinder; a pump piston moveably mounted in a recess of the pump cylinder, the pump piston being moveable up and down in the recess; and a leakage groove arranged in the pump cylinder in a region of the recess, the leakage groove being coupled with a leakage line configured to discharge a fuel leakage. Between the pump cylinder and the pump piston a different size pairing clearance is formed in first and second portions of the pump cylinder.

A piston pump as a high-pressure fuel pump of a common rail system includes: a pump cylinder; a pump piston moveably mounted in a recess of the pump cylinder, the pump piston being moveable up and down in the recess; and a leakage groove arranged in the pump cylinder in a region of the recess, the leakage groove being coupled with a leakage line configured to discharge a fuel leakage. Between the pump cylinder and the pump piston a different size pairing clearance is formed in first and second portions of the pump cylinder.

A fuel injection pump includes a cylinder formed with a passage of fuel, a plunger, and a swirl flow generating par. The plunger slides along an inner wall of a sliding hole located in the cylinder and reciprocates between an uppermost point and a lowermost point to pressurize the fuel in a pressurizing chamber placed at an end of the sliding hole at a highest point. The plunger is movable downward to cause the pressurizing chamber to inhale the fuel from an intake passage in a fuel suction stroke. The intake passage is communicated to the pressurizing chamber at a lateral side of a plunger axis that is an axis of the plunger in a sliding direction. The swirl flow generating part guides the fuel to form a swirl flow around the plunger axis in the fuel suction stroke.

A fluid pump includes: three or more volume chambers that suction and discharge a fluid sequentially; moving elements that are respectively provided in the volume chambers, move relative to the volume chamber, and suction and discharge the fluid from and to the volume chamber; a cam that abuts against and drives the moving elements; and a driving section that drives at least one of the moving elements and the cam and relatively rotates the moving elements and the cam to discharge the fluid one time from each of the volume chambers in one cycle of the relative rotation, in which, when suctioning and discharging the fluid, regarding a discharge rotation angle α, α=(Z/M)×N is satisfied, where the number of volume chambers is M and any integer from 2 to (M−1) is N.

A fluid pump includes: three or more volume chambers that suction and discharge a fluid sequentially; moving elements that are respectively provided in the volume chambers, move relative to the volume chamber, and suction and discharge the fluid from and to the volume chamber; a cam that abuts against and drives the moving elements; and a driving section that drives at least one of the moving elements and the cam and relatively rotates the moving elements and the cam to discharge the fluid one time from each of the volume chambers in one cycle of the relative rotation, in which, when suctioning and discharging the fluid, regarding a discharge rotation angle α, α=(Z/M)×N is satisfied, where the number of volume chambers is M and any integer from 2 to (M−1) is N.

An improved high-pressure fuel pump for a gasoline direct injection system is provided. The fuel pump includes a pump body defining a low-pressure side, a high-pressure side, and a pumping chamber therebetween. The pump body also defines a central bore and a drain port extending from the central bore to the low-pressure side. A slip-fit sleeve is clamped within the central bore, the slip-fit sleeve including upper and lower guide ribs. A plunger is moveable within the sleeve for compressing fuel within the pumping chamber. The plunger and the sleeve define a first diametral clearance, and the guide ribs and the central bore define a second diametral clearance. Fuel diverting around the upper guide rib during pumping operations can recirculate through the drain port to the low-pressure side. To accommodate thermal expansion of the sleeve, the second diametral clearance is at least 75% of the first diametral clearance.

A piston pump for a high-pressure cleaning device is provided, having a pump housing, which includes a first housing part and a second housing part. The first housing part forms a suction conduit and a pressure conduit, and the second housing part forms a plurality of pump chambers into each of which a reciprocally movable piston dips and which are each in flow connection with the suction conduit by way of an inlet channel and with the pressure conduit by way of an outlet channel. The inlet channel can be closed by an inlet valve and the outlet channel can be closed by an outlet valve. The second housing part includes a valve receptacle, and that the piston pump includes an outlet valve assembly, wherein the outlet valve assembly comprises an outlet part, which is inserted into the valve receptacle and forms all outlet valve seats.